A change in an ecosystem necessarily affects the species which are part of it, and changes in species in turn affect ecosystem processes. ... This is caused by the extinction of species or loss of populations that had been unique to particular regions and by the invasion or introduction of species into new areas.
Decomposers and scavengers break down dead plants and animals. They also break down the waste (poop) of other organisms. Decomposers are very important for any ecosystem. If they weren't in the ecosystem, the plants would not get essential nutrients, and dead matter and waste would pile up.
Plants add water to the atmosphere through transpiration. Transpiration is the process of water moving through plants and evaporating, becoming water vapor. This water vapor is released into the atmosphere.
